47 lines
883 B
Plaintext
47 lines
883 B
Plaintext
# lib queue.nas
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# valkmjolnir 2021/3/31
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var queue=func()
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{
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var (begin,end)=(nil,nil);
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return
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{
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push:func(elem)
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{
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var new_node=
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{
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elem:elem,
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next:nil
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};
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if(begin==nil)
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begin=end=new_node;
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else
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{
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end.next=new_node;
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end=new_node;
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}
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return;
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},
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pop:func()
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{
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if(begin!=nil)
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begin=begin.next;
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if(begin==nil)
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end=nil;
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},
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front:func()
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{
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if(begin!=nil)
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return begin.elem;
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return nil;
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},
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clear:func()
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{
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begin=end=nil;
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},
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empty:func()
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{
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return begin==nil;
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}
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};
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}
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